Explore the maze and look for the switch that turns off all the defective robots.

ATM1) the switch is missing :-)2) bullets for MC are missing (also robot testing collision of bullets against robots)3) robot explosions (but some code is there)4) MC die (now you just start the game again)

I know that is insane; but if you're seeking some more bytes at all cost you can try to shuffle the order in what the subroutines are in memory. Simply changing their positions you can get back dozens of bytes

Also that MSX-O-Mizer thing sounds interesting, it's really better than BB or Pletter?, and how about speed (although decompress an executable is not a task that needs too much speed)?

Also that MSX-O-Mizer thing sounds interesting, it's really better than BB or Pletter?, and how about speed (although decompress an executable is not a task that needs too much speed)?

Yes, MSX-O-Mizer is better than pletter5b.The depacker routine is shorter and the compression gain, on my 2K files (i.e. pure asm code and few data), is about 4%-8% depending on the size and on the type of data. Actually I've found even larger gains when compressing larger files (12% of gain against pletter for screen 2 images).

The contra are:1) it is slower, but I cannot say how much wrt pletter2) it needs some bytes of ram as temporay buffer